"为了祈求好运" can be translated into English as "in the hope of attracting/inviting good luck" or "to pray for/seek good fortune".
Here are some example sentences:
They perform certain rituals in the hope of attracting good luck.
（他们进行某些仪式，以祈求好运。）
People light candles to pray for good fortune during the festival.
（节日期间，人们点蜡烛祈求好运。）